Aeroplane flying-machine.



J. S. STEPHENS.

AEROPLANE FLYING MACHINE.

APPLICATION FILED JULY 5, 1910.

Patented Feb. 2, 1915.

7 SHEETS-SHEET 1.

J. S. STEPHENS.

AEROPLANE FLYING MACHINE. APPLIGATION FILED JULY 5, 1910.

1,127,105. Patented Feb. 2, 1915.

7 SHEETS-SHEET 2.

J. S. STEPHENS.

AEROPLANE FLYING MACHINE.

APPLICATION FILED JULY 5, 1910. 191 273%, Patented Feb. 2, 1915.

' r 7 SHEETS-SHEET a.

23 fie- 96. 22

JVS STEPHENS.

AEROPLANE FLYING MACHINE.

APPLICATION FILED JULY 5, 1910.

Patented Feb. 2, 1915.

7 SHEETS-SHEET 4.

gb g

J; s. STEPHENS.

AEROPLANE FLYING MACHINE.

APPLICATION FILED JULY 5, 1910.

1,127,105, Patented Feb. 2, 1915.

7 SHEETS-SHEET 6.

I. S. STEPHENS. AEROPLANE FLYING MACHINE.

APPLICATION FILED JULY 5 1910 1,127,1050 Patented Feb.2,1915.

7 SHEETS-SHEET e.

J. S. STEPHENS.

AEROPLANB FLYING MACHINE.

APPLICATION FILED JULY 5, 1910.

Patented Feb. 2, 1915.

7 SHEETS-SHEET 'l.

JAMES S. STEPHENS, OF CHICAGO, ILLINOIS.

AEROPLANE FLYING-MACHIN E.

Specification of Letters Patent.

Patented Feb. 2, 1915.

Application flied July 5, 1910. Serial No. 570,419.

To (.171 zr/eom 2'1- may concern:

Be it known thatl, JAMES S. STEPHENS, a citizen of the United States of America, and a resident of Chicago, county of Cook,

State of Illinois, have invented certain new and useful Improvements in Aeroplane Fly- 1ng- .\Iachines, of which specification.

The main objects of this invention are to provide an improved form of aeroplane fly-- ing machine in which steering in any direction may be accomplished by relative move-' will a o d the necessity of vertical rudders.

fins. heels. or similar constructions. which do not coiperate directly in the support of the mach ne; to provide an improved shape for aeroolanes whereby the air pressure will be so distributed as to compensate'for disturbances of lateral balance and tend to automa ticallv correct the same: to provide an impro ed construction and locat on of the steering aeroplane whereby it will serve to maintain lateral balance of the machine besides controlling the direction of mo ement thereof: to provide an improved formation for the advancing edge of an aeroplane: and to provide an impro ed fo m and arrangement of the aeroplane surfaces in biplane constructions whereby the efficiency of the supporting surfaces will be increased and whereby the efiective area of the supporting surfaces will be reduced as :the speed increases.

An illustrative embodiment of this invention is hereinafter describ d and is shown in the accompanying drawings, in which Figure 1 is a front elevation of an aeroplane fiving machine of the bi-plane type, constructed according to this invention. Fig. '2 is a side elevation of the same. showing the same in the normal att tude of flight,

the lines A, B and C representing a horizontal surface corresponding to the respectivethe following is aattitudes of the machine when at rest on the ground, when in flight and when commencing to alight, it'being understood that the rear wheels will yield under the weight of the machine and touch the line A when the machine is at rest. Fig. 3 is a top plan partly broken away. Fig. 4: is a sectional detail of the ball and socket joint on which the steering plane turns Fig. 5 is an enlarged sectional detail, showing the method of mounting the steering aeroplane. Fig. 6 is a front elevation of the steering aeroplane. the adiacentjparts of the supporting frame being shown in section. Fig. 7 is a detail showing the air bags between the up per and lower coverings and the frame members of the main supporting aeroplanes. Fig. 8 is a fragmentary top plan illustrating the same feature. Fig. 9 is a detail of the main controlling lever and its rocking handle bar. Fig. 10 is another sectional detail 4 of the joint shown in Fig. 4. Fig. 11 is a detail in top plan of the joint which supports the operating le er. showing in connection therewith the tiller arm which causes the steering of the machine when sup orted on its wheel's. Fig.12 is a side ele ation of the same viewed from the right of Fig. 11. Fig. 13 is a sect onal detail of the same taken on a plane parallel with that of Fig. 12 and pass ingth ough the. center of the io nt. Fig. 14 is a diagram showing in isometric perspec-1 t e the arrangement of the steering devices. Fig. 15 is a detail in perspective showing the method of bu ding up the framewo k of the aeroplanes. Fig. 16 is a d ag ammatic front elevation showing the lateral curvature of the u per aeroplane. and also showing the variation in the inclination of the fore and aft elementsofthe surface whereby the m d dle art of the plane hasa greater. angle of incidence to the air than do the lateral extrem ties'. the full lines ind cat ng the sha e of the front edge of the plane and the dottedline ind cat n the sha e of the rea. edge the eof. This figure shows the plane in such posit on that when it is advanced hori-. zontally the lifting effect of the m ddle por-' tionis co nteracted b the depressing effect of the end portions. the effect of gravity being neglected. Fig; 17 is a s milar view of the same turned to such pos t on that its entire lower sur ace will pro de lift ng effect in horizontal fl ght. also ind cat ng the lo er plane. Fig. 18 is a sectional detail of. the

joint between the ribs and the rear edge of the frame member of the aeroplane construction illustrated in Fig. 15. Fig. 19 is a diagram showing by singe lines the differences in the lateral curvature of the planes in the biplane construction illustrated. Fig. 20

' tending, in the direction of flight, through the center of effort of the front planes, such a. line being representedat D. Fig. 21 is a diagrammatic front view illustrating how the leverage of the steering plane may be utilized for maintaining lateral balance when placed above a line through the center of effort of the front plane and parallel with the direction of flight. Fig. 22 is a diagram illustrating the tendency of the upper plane to assume a position of equilibrium.

In thespecific construction illustrated in the drawings, the support of the machine on the air is accomplished by the main aeroplanes 1 and 2 acting in conjunction with the-steering plane 3. These planes are curvedin the fore and aft direction in the usual manner to provide a downwardly concave lifting surface. The surface of each of the planes is so formed as to be symmetrical with respect to a vertical plane of reference extending fore and 'aft through the middle. of the machine, which plane will hereinafter be-referred to as the plane of symmetry. (See line S, Fig. 19). Y

The parts of the plane 1 which are .at opposite sides of the plane of symmetry are in dihedral relation to each other, being inclined upwardly and away from the center line.

The plane 2 is of downwardly diverging dihedral form at its middle part, and its lateral curvature changes so that its end portions areof upwardly diverging dihedral form. The degree of lateral curvature of the middle portion of the plane 2 is substantially the same as that of the middle portion of the plane 1, and this curvature than the lower plane. 4 This, together with I the fact that the upper plane is extended laterally beyond the ends of the lower plane, serves to neutralize the effect of the deflection of the air by the lower plane, and to compensate for the reduced speed of the cur-' rent of air below the upper plane due to the resistance offered by the parts of the machine between the planes. This serves to increase stability and to equalize the actual lifting effect of both planes. Stability is also increased by having the lifting effect greater. in the middle than at the ends of the planes. On account of this twist, or-warp in the planes land 2, the effective area of the supporting surface of the machine will be gradually reduced as the machine tilts forward, thus permitting the effective area of the supporting surface to be adjusted to suit the speed of advance and permitting horizontal flight ,at different speeds. This twist is best seen in Fig. 17, in which the front edges of the planes are represented diagrammaticallyby full lines and the rear edges by dotted lines. From't his figure it will be seen that the machine may be tilted forward,funtil the only effective supporting surface will be the middle portion of the upper plane. tions of the steering plane 3 are also disposed in dihedral relation to each other with re spect to thefore and aft plane of symmetry and are inclined upwardly similarly to those of the plane'l.

The body frame of the machine comprises the supporting frames of the main aeroplanes 1 and 2,.the bracing between them and a rearwardly extending frame or fuselage l. Rigidly braced below the body-frame is a long skid 5, the rearward portion of which extends a considerable distance beyond the rearward braces 6, and acts as a spring to yieldingly engage the ground to check the advance of the machineasit alights. The skid 5 curves upwardly at its front end where it is suitably braced by a truss structure represented by the members 7 and 8 (Figs. 2 and In the-drawings, the truss constructions are represented more or less diagrammatically, no attempt being made to show the details of the joints, and in some places the bracing is omitted -in orderto avoid confusion of the drawings. From Fig. 3 it will be seen that there is but one skid 5, and that the front and rear portions of the body frame are lan.

The alighting gear comprises, besides the skid 5,-a set of wheels, of which in the form shown there are three, that is, a pair of rear wheels 9 and a front steering wheellO, mounted in a fork 11 at the, front of the body frame and elevated a considerable dis tance above the wheels 9'when the machine is in the normal attitude of flight, as'represented in F ig.x2 with reference to the line A as the horizontal. I

The wheels 9 are carried by forks 1'2 journaled on vertically disposed axes in swingtriangular in ing frames 13 hinged at their rearward ends The lateral porcushions indicated by the cylinders 14, but

not shown in detail.

The steering plane 3 has ball and socket connection with the rearward upright 15 of the body frame, as detailed in Figs. 4 and 10, the socket members 16 being rigidly connected to the framework of the plane 3 and the ball 17 being longitudinally slidable on the upright 15. The upward movement of the plane 3 is limited by means of two braces 18 and 19, which are located below the plane, 3 at opposite sides of the ball 17 in the fore and aft plane of symmetry, their lower ends being secured to a fitting 20 on the body frame and their upper ends being secured to depending arms 21 connected to the framework of the plane 3. These arms might be termed fulcrum arms since under certain conditions of flight their points of connection to the stays 18 and 19 serve as fulcrums about which the plane 3 turns, as will hereinafter appear. A pair of spring stays 22 are located above the plane 3 in the fore and aft plane of symmetry and respectively in front of and behind the brace 15 to support the weight of the plane 3 when the machine is at rest.

The steering plane 3 is rigidly braced and trussed as indicated in Figs. 5 and 6, and its truss comprises a pair of uprights or masts 23 which are spaced apart and in such positions with respect to the center of the ball 17 that their ends are all substantially in the same plane with said ball and I symmetrically located with respect thereto.

The operating mechanism by which the steering plane is controlled, comprises a lever post 24 mounted in a fitting 25 which permits it to rotate about its own axis and to oscillate in a fore and aft plane parallel with the pl ne of symmetry of the machine.

- The post 24 has a cross-bar 26 at -its lower end and a handle-bar 27 at its upper end.

The cross-bar and handle-bar are of substantially equal length and connected to the post 24 at their middle points, and their extremities are respectively connected with the extremities of the masts 23 of the plane 3 by cables 28 and'29. thecables which are on the same side of the fore and aft plane of svmmetry of the machine being crossed as shown in Fig. 2. Thus. a fore and aft oscillation of the post 24 will cause an equal angular movement of the uprights 23 in the reverse direction and tilt the steering plane 3 for steering up or down. Rotation of the post 24 about its own axis will cause a similar and equal angular rotation of the plane 3. The handle-bar 2.7 is pivotally connected at 30 to. the post 24. the axis of the connection30 being at right angles to the axis of oscillation of the post 24. Cables 31 connect opposite sides of the handle-bar 27 to opposite sides ofthe steering plane 3. The cables 31 pass over sheaves 32 and 33.

which are respectively located as close as possible to the center of movement of the post 24 and to the axis of thestrut 15, so that the cables 31 will not be affected by the normal rotation of the pot 24 during steering operations, but will only be affected by the rocking of thehandle-bar 27 upon its pivotal connection 30. In order to have the cables 31 lead in a direction substantially with a tiller 39, which is rigidly secured to the rotatable gimbal ring in which the post 24 is pivoted. The post 24 may thus be oscillated in a vertical plane without affecting the tiller, but when the post 24 turns about its axis, .the tiller turns with it.: If the tiller 39 extends. in a forward direction, as shown. then the cables 38 should be crossed so that the operation of the steering handlebar will be the same for steering on land as for steering sidewise in the air.

A form of joint suitable for supporting the post 24 and permitting of the necessary movements thereof is illustrated in detail in Figs. 11, 12 and 13. A bearing collar 41 is fixed at the middle of the post 24 and a pivot bolt 42 extends through the collar 41 and post 24, and has its ends seated in a gimbal ring 43 which is journaled at its periphery in fitting 44 secured to an adjacent part of the body frame of the machine by'the bolts 45, which also serve as axles for the sheaves 32, whichare housed within slots in the fitting 44, as shown in Fig. 11. The fitting '44 forms a band which embraces and serves as a bearing for the ring 43, and for convenience of assembling, the fitting 44 is split on the line 46, the two parts being held together by the bolts 45. The bolts 47 which secure the tiller -39 to the ring 43 extend through holes in the ends of the bolt 42. as will appear from Figs. 11

and 12, and thereby lock said bolt 42 against shifting. i I

The framework of the aeroplanes also comprises novel features of construction, as

will appear from Figs. 15 and 18. Inthe form shown, eachaeroplan'e comprises two l per and lower edges of these webs of fiber are reinforced by strips or beads of wood 51, which are slotted to receive the edges of the web, and are secured in position. by means of glue, or other fastening. By this construction, a rib of I-shaped transverse section is produced which has great strength in proportion to its weight.

In large machines, where the spars 48 are widely separated, one or more additional transverse members 53 may be provided. Such an additional transverse member is shown in Fig. 15. This member is built 'up of upper and lower wooden strips or beads 54, with an open web 55 formed of vulcanized fiber as inthe rib construction.-

The strips 54 are grooved lengthwise to receive the web 55 wh1ch braces them apart, and are grooved transversely in their respective upper and lower surfaces to fit the webs of the ribs to brace them laterally. In the construction shown, the transverse member 53 extends'through the lightening holesin the ribs. The diagonal bracing is preferably formed of flat wire 56, similar in cross-section to a clock spring, and is twisted so that at the intersections the braces will lie flat, one upon the other.

The frame members 57, which extends along and gives stiffness to the front edge of the aeroplane, is preferably of triangular shape so as to present a sharp edge 58 to f the air, and is hollowed out as shown, for

.the sake of lightness. The upper surface of "the member 57 is fiushwith and forms a continuation of the upper -surfaces ofthe ribs 49. The lower surface of the member 57 is flush with the lower surface of the ribs 49 at its rearward edge, and is curved sharply upwardly so as to meet the upper surface atthe edge 58. By this construction, all of the air which impinges against the member 57 in flight is deflected downwardly and increases the lifting pressure on the lower surface.

The upper and lower beads of each rib are brought together at the rearward end:

of the-rib, as illustrated in Figs. 15 and 18, and are then together she ed to cylindrical form so as to fit a cylindrical bore in the member 59 which connects the rearward ends of the ribs. The web 49 of vulcanized fiber is also preferably extended to the end of the rib so as to give strength to the cylindrical end parts which engage the member 58.

In orderto give sufficient buoyancy to the machine, in case it alights upon the water, to support the engine 'clear of the water. sections of inflated pig gut are packed into the spaces between the frame members and the upper and lower coverings of'the planes 1 and 3. These are indicated at 52 in Figs. 7 and 8.

' The operationof the device shown is as follows :-The machinerests on the ground in the attitude indicated in Fig. 2 with reference to the line A as the horizontal, and when it is in this position, its planes are so disposed as to beneutral as regards lifting effect, and therefore ofier minimum resistance to advance of the machine along,

the ground. In starting, the machine is first driven along the ground, andas soon as 1t acqu1res SUlIlClQHt speed, the operator tilts the steering planeforward so as to depress the tail of the machine slightly, giving lifting effect to the main planes, and causing the machine torise from the ground. As the machine commences to rise, the load on the rear wheels will become gradually less, and these wheels will accordingly be pushed downward by the compressedairin the cylinders 14, and prevent the rear end of the skid from striking the ground. When the machineis flying horizontally,its normal attitude is that shown in Fig. 2, with reference to the line B as the horizontal.

It will be noticed that when the machine is i in this attitude, the steering plane 3 is located -at' considerable height above the horizontal plane extending through the resultant center of effort of the planes 1 and 2. This center in the particular designshown is located approximately at the point E in Figs. 2 and 20. This relation of the aeroplanes is best understood from the diagrammatic views 19and 20. From these views it will be seen that when the resultant pressure on the steering plane 3 is directed toward either side of the plane of symmetry of the machine, it exerts a force tending to turn the machine aroundan axis extending through the center of effort E of the main plane and parallel with the line of flight, which force is utilized in the herein described invention for maintaining lateral balance ofhthe machine, and correcting a tendency of the same to tip, whatever may be the cause of such tipping.

In view of the absence of rudders, keels and like structures, tending to prevent the steering'plane from moving edgewise in alateral direction, steering in horizontal directions with the device shown is accomplished in a manner entirely different from-that of usual forms of aeroplane flylng machines, where horizontal vertical fins,

the machine, due 'to the fact that the lift ing effect of the main planes is less on the herein shown, and in the absence of vertical rudder surfaces, the turning of the steering plane causes the machine to turn in a direction opposite to that which would be the case if the steering were accomplished by avertical rudder surface, and the tipping of side thereof which is traversing the .arc of least radius in turning a curve, is counteracted by the leverage of the steering plane due to its location above the line D of Fig. 20, so that the correction for disturbance of lateral balance during turning ismainly accomplished automatically by the steering plane itself, without relying upon the use of ailerons or wing warping devices, which are resorted to inusual constructions. The lateral tilting of-the aeroplane 3 by tilting the handle-bar 27 enables the operator to increase or decrease the balancing efiect sons to correct any disturbance of lateral balance which is not corrected automatically by the turning of the steering planeabout its vertical axis. a

In the form of machine shown in the drawings, the center of effort E of the main planes 1 and 2, the center of effort 1* of the steering plane 3, and the center of gravity G of the machine and its load are all in the fore and .aft vertical plane of syinmetrv of the machine, the center F being above and also spaced horizontally away, from the center E, and the center G being below the center E and between the centers E and F. Such an arrangement insureslnherent stability and renders effective both the steering and balancing functions of the steeriiig plane. lVhen the steering plane is above a line drawn through the center of effort E, and parallel with the direction of flight, it will tend to come down into the plane of flight represented by the line D of rig. 20, but this tendency is counteracted by the lifting effect of the plane 3, and there is thus available for control a positive leverage.

Tosteady the lateral sliding of the'ste ering plane, which is relied upon for steering purposes, and also to assist in giving the machine inherent stability tending to keep it upright under all conditions, the steering plane, in the form shown, has. its lateral side portions inclined dihedrally with respect to each other, the inclination being upward and away from the fore and aft vertical plane of symmetry. This dihedral formation of the steering plane provides a certain amount of lateral drift ornresistance to cdgewise motion, which, while not suflicient to render ineffective the steering principlewhich is relied upon and which has been hereinbefore described, reduces the lateral movement to a desirable extent and prevents sudden shifting movements of the machine,

'which occur, in machines having planes which are straight laterally from end to en During flight the lifting eflect of the steering plane 3 is transmitted to the body frame through one or both of the stays 18 and 19, depending upon whether or not the strain is removed from-one of them by a strain upon the cables 28 or 29. These stays, being respectively fore and aft of the center .of eflort of theplane, determine its normal fore and aft inclination. They are adjustable, and the plane may therefore be set to what is found by experience to be the best angle for any particular design of machine. A strain upon the cables 28 and corresponding slackening of the cables 29 causes a slackening of the forward stay 18 and causes the. rearward stay .19 to carry the entire upward pull of the plane 3. Similarly, a strain upon the cables 29 shifts the load to the forward stay 18. The fact that the stays 18 and 19 are connected to the plane 3 at points below the center of efl'ort of the plane 3 insures that under normal conditions this plane will assume its normal position with respect to theplane of symmetry of the machine, and will not have a tendency to tip laterally in either direction, except when such lateral tipping iso produced by tipping of the handle-bar 27. In

order to provide suitable points of attachment for the stays 18 and 19, the framework of the plane 3 i s extended to the desired position below the center of effort by means of the arms 21..

diverging dihedrallform. These upwardly turned lateral extremities of the upper plane 2 insure that in case the machine tipstoward one side and tends to glide -sidewise,'it will glide toward the low side and be swung toward its normal horizontal position by the rudder effect of the upturned advancing edge of the plane. Thus, as the center of gravity is below the resultant center of.

effort of all the planes,

The center of gravity should be so place with respect to the centers of efiort of the supporting aeroplanes that the machine will normally assume a forward gliding angle as soon as the driving power of its engine ceases.

The inherent lateral stability of an aeroe machine will nats 'urally assume an upright position. T

plane having a lateral curvature similarto that of the plane 2, and carrying weight so that the center of gravity is below'the aeroplane, will be understood from a consideration of F ig. 22, in which the aeroplane is shown tilted toward one side, and the center of gravity is represented at G below and in the plane of symmetry of the aeroplane. On account of the inclination of the plane, it will glide in a downward direction toward the left, but on, account of the curvature of the plane, it will be swung toward a horizontal position. This movement is still further assisted by the fact that the left-hand side of the plane is pre sented to the upward pressure of the air at a more effective angle than the right-hand side, and the resultant upward pressure of air will therefore be at a considerable distance at the left of the middle line of the plane, as for instance, at the point represented by. the arrow 61 As soon as the plane returns to its horizontal position, 1ts form will tend to hold it in equilibrium, aso the strongest upward pressures will be concentrated at the middle, and any departure from the horizontal position immediately brings intoaction the stabilizing power of the upwardly curved ends. In addition to the stabilizing influences which are inherent in the various planes by reason of their form and relative location, there is, in the construction shown, the very important stabilizing property of the steering plane which is controllable by the operator, namely, the lateraltilting of the steering .planeby tilting of thehandle-bars. The effect ofthis tiltingisobvious from Fig. 21, if one bearsin mind the fact that the pressure of 'airagainst a surface is normal tothe surface. From Fig. 21 it will be seen that when the steering plane is in its normal position, as indicated by the horizontal line,

the resultant pressure on it is directed upward in the plane of symmetry pf the machine, but when it is tilted toward either side, the pressure, as indicated by the small arrows in Fig. 21, is directed toward the corresponding side, and as these resultant pressures act at a distance from the line extending through the center of effort of the main planes in the direction of the line of fiight, the steering planewill, when tipped sidewise, .in one direction, tend to counteract any tendency of the machine to tip in the opposite direction. The fact that this lateral tilting is controlled by the mere rocking of the handle-bar by means of which the. operator accomplishes the normal steering function, makes the control of the machine extremely simple. The operator turns the post 24; in the direction in which he wishes the machine to turn. This. as has been described. causes the turning of the machine; The disturbance of lateral balance which resultsiin turning, from the fact that one side of the main plane travels-in an arc of shorter radius, and therefore at slower speed than the other side, is offset by the lateral pull of the steering plane, by virtue balance the tendency of the main plane to tip, and inthis case, the operator merely tilts his handle-bar sidewise enough to counteract such insufliciency or excess.

As has been described, the universal. joint about which the steering plane turns is located substantially at or near the normal center of pressure of the air on said plane. This, with aeroplanes of usual form, is in the plane of symmetry of the aeroplane, and

at a distance equal to about one-third of the width of the plane rearward from its front edge. lVith this arrangement, the pressures on the steering plane are approximately balanced with respect to the center of movement, regardless of the angular position of the plane. When the angle of incidence of an aeroplane is changed within the limits suitable for flight, its center of effort shifts slightly in a fore and aft direction. The fulcrum arms 21 are spaced away from the universal joint sufliciently far in a fore "and aft direction to insure that the center of effort will at all times lie between them, and the length of the arms 21, and their distance from the center of ,universal'movement are so proportioned that the plane will normally return to its nbrmal position for horizontal flight, but will require the expenditure of but a small amount of power to tilt it.- Practically all of the lateral pull of.the steering plane when tilted laterally is transmitted to the frame of the machine through the universal joint and the strut 15, whereas, the only power which (the operator must exert in ,order to keep the plane tilted is enough to tilt the plane against the down ward pull of the stays 18 and 19 upon the fulcrum arms when said arms are displaced from a vertical .position by the tilting of the plane. This is usually only a comparatively small component of the upward pull of the steering plane upon the stays 18-. The lower plane 1 and the steering plane 3 also have inherent lateral stability due to their upwardly diverging dihedral form, as is well known. All of these features combined tend to promote normal stability, which will insure that the machine will advance straightaheadin an upright position in case of accident to the operator, or the controlling mechanism, or in case the operator lets go of the handle-bars, regardless of whether the machine is driven by its motor or merely gliding- It is well known that in bi-plane's, the

lower plane has the effect of deflecting the air above it to such an extent as to greatly reduce the lifting efliciency of the upper plane. This fault is further accentuated by the resistance which is offered by the structure of the machine. In order to counteract this fault, the body frame is so constructed that the upper plane will always have a greater angle of incidence than the lower plane, and the upper plane is extended laterally beyond the ends of, the lower plane so as to reach air which is undisturbed by the lower plane.

From Figs. 15 and 16, it will be noticed that the fore and aft elements of the main planes are so disposed that each will have a greater angle of incidence at its middle part than at its ends. This has the important advantage of reducing the effective area of the main planes as the machine increases its speed, and therefore makes horizontal flight possible with a large range of speed varia-v tion. As the speed increases, the angle of incidence of the main planes is reduced, and as the angle of incidence of the main planes is reduced, the end portions first of the lower plane and then of the upper plane move toward positions .in which they have no angle of incidence, or a negative angle of incidence. With these planes shaped as shown, maximum lifting effect is always in the center, and does not shift rapidly from side to side with change of transverse level, as is the case with planes which have a straight transverse form with the same angle of incidence from end to end.

As the machine approaches the ground to alight, the operator tilts the steering plane 3 forward so as to reduce its angle of incidence, and thereby reduce its lifting effect until it assumes the attitude indicated in Fig. 2 with reference to the line C as the horizontal. Then the main planes 1 and 2 are at their maximum angle of incidence, which increases their head resistance and the rearward end of the spring skid 5 engages the ground, all tending to reduce the speed of advance of the machine. As the skid extends a considerable distance "rearward of the center of gravity, the machine gradually tips forward as the lifting effect of the planes 1 and 2 is-reduced by the reduction of speed. As the machine tilts forward, the wheels 9 engage the ground, and then after further reduction-of speed and lifting effect of the planes, the wheels 9 yield and the machine continues to tip forward until it rests upon the three wheels in the attitude represented by Fig. 2, with reference to the line A, as the horizontal. The center of gravity will now be between the wheels. and the machine will rest in stable equilibrium. J

The design of the machine is such that the center of buoyancy of the air cells in the aeroplane lwill be in advance of the center of gravity, so that the machine will float in an upright position when supported on the water. L

The balancing influence of the steering plane 3, aside from the stabilizing effect of the main planes, when the machine is tipped toward one side, will be more clearly understood from Fig. 21, if we assume that the machine is tipped toward one side, so that the vertical line through the center of gravity is represented by the line V in said figure. If, when the machine istipped to this position, the plane 3 is turned to a horizontal position represented by the line 3, which is at right angles to the line V, the upward pressure on the steering plane will coact with the downward pull of gravity, and tend to turn the machine about an axis extending through the resultant center of effort of 'all of the planes in the direction of flight, and this corrective influence, as will be seen from Fig. 21, is mainly proportional to the distance of the steering plane from such axis. The fact that the steering plane is of dihedral form, and is secured to the frame of the machine at a. point below its center of effort, will cause it to tend to assume a horizontal position at all times. This stabilizing effect of the plane is therefore automatic, and does not i require thought on the part of the operator.

Although but one specific embodiment of this invention is herein shown, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention, as defined by the following claims.

I claim 1. In a flying machine, the combination of a plurality of aeroplanes located one behind and above another in the normal attitude of the machine for horizontal flight, a frame connecting them, the rearward one of said aeroplanes being mounted in said. frame to rotate about a vertical axis and being tiltable in both fore and aft and lattially in said axis, and means acting between said rearward aeroplane and said frame and adapted through the pressure on said steering aeroplane to cause the same to tend to assume its normal position, and thereby tending to urge the machine toward its normal attitude for horizontal flight.

2. In a flying machine, the combination of a plurality of aeroplanes located one behind another, a frame connecting them, said frame comprising an upright extending through the rearward one of said aeroplanes, 2. universal joint connecting said upright with said rearward aeroplaneand vertically movable along said upright,

means for tilting said rearward aeroplane 'eral directions about a center lying substanto various angular positions with respectto said upright, and means connecting said rearward aeroplane to said frame and adapted through the air pressure on said rearward aeroplane to urge it to a certain predetermined position with respect to said frame. r

3. In a flying machine, the combination -of a plurality; of aeroplanes located one be said rearward aeroplaneabout the axis of said upright, and means connecting said rearward aeroplane to said frame and adapted through the air pressure on said rearward aeroplane to urge it to a certain predetermined position with respect to said frame. y

4. In a flying machine, the combination of a plurality of aeroplanes locatedone behind another and one beingrelatively movable for steering, a frame connecting them, said frame comprising anupright extending through said steering aeroplane, a universal joint connecting said upright,with

said steering aeroplane and vertically move able along said upright. stays for limiting.-v the upward movement of said steering aeroplane on said upright and secured'to said steering aeroplane at] points below the center of said universal 'joint and respect vely in fr'ont'of and behind said upright,rwhereby I said steering aeroplane will normally assame a position of-equlibrium symmetrical I with respect to a vert cal plane extending through said universal'jointin the direction of flight, and means independentof the pressure on said steering aeroplane and i being thereby adapted to steer the machine. both horizontally and vertically and to maintain lateral and longitudinal balance, sai'd' yieldingly supporting the weight thereof. 5. In a flying machine, the combination of. aframe, a pluralltyof aeroplanes coacting in the support of the machine, 'oneof,

said aeroplanes being mounted to have universal-movement about a center located'inward of its marginal edges and-being adapted'through suchmovement to steer the machine, and means connecting said movable aeroplane to said frame and adapted through the pressure of the air on'said mov-.

able aeroplane to normally urge said movable aeroplane to a certaindefinite position with respect to the frame and thereby tending to urge saidmachine toward its normal attitude for'horizontal flight.

,6. In a flying machine, the combination of a plurality of aeroplanes located one be.- hind another and one being relatively movable forsteerin'g. a frame connecting them,

said frame comprising an upright'extending through said steering aeroplane, a universal joint connecting said upright with said steering aeroplane and vertically movable along said upright, stays for limiting the upward movement of said steering aeroplane on said upright and secured to said steering aeroplane at points below the center of said universal joint and respectively in front of and behind said upright, whereby said steering aeroplane will normally assume. a position of equilibrium symmetrical with respect to a vertical plane extending through said universal joint in the direction of flight.

, 7. In a flying machine, the combination of a plurality of aeroplanes located one behind another and one being relatively movable for steering, a frame connecting them, said frame comprising an upright extending through said steering aeroplane, a universal joint 1 connecting said upright with said aeroplane and vertically movable along said upright, stays for limiting the upward movement of said steering aeroplane on said upright and secured to said steering aeroplane at points below the center of said universal joint and respectively in front of and behind said upright, whereby said steering aeroplane will normally assume a posi- 4 tion of equilibrium symmetrical with reit upward to maintain a tension on said stays.

8. In a flying machine, the combination of a main;aeroplane structure, a body frame connected in rigid relation to said main aeroplane structure, a steering aeroplane coacting with said-main aeroplane structure in the support of the [body frame 'and mounted tohave universal movement with respect to said main aeroplane structure and steering aeroplane being mounted so that its center of universal movement may be capable of vertical movement 1n said frame, a

pair of tension stays secured to said steering. aeroplane at points within the plane of ment and also below and out of alinement therewith, whereby the air pressure upon said steering aeroplane will normally urge --1t to a certain initial. dispositl on wlth respect to said frame.

9. In a .flying machine, the combination of avsupporting frame, a steering plane said frame and adapted to permit said plane to move vertically to a limited extent at said center of universal movement, and a pair of fulcrum arms on said plane, means connecting said fulcrum arms to said supporting frame, said fulcrum arms being located at opposite sides of the center of universal movement of said steering plane and in the fore and aft line of symmetry thereof, and being located below said center so that the air pressure on said steering plane will normally hold it in a substantially horizontal position.

10. In a flying machine, the combination of a supporting frame, a steering aeroplane symmetrically shaped with respect to a fore and aft vertical plane of symmetry and mounted to have universal movement about a center located substantially in the fore and aft vertical plane of symmetry, means connecting said steering aeroplane with said supporting frame, being connected to said steering aeroplane at a point below the center of effort thereof and in said fore and aft plane of symmetry, whereby the air pressure on said steering aeroplane will normally urge it to assume a certain normal disposition with respect to said frame.

11. In a flying machine, the combination of a main aeroplane structure, a steering aeroplane symmetrically shaped with respect to a vertical plane parallel with the normal direction of flight, a vertically disposed member connected With said main aeroplane structure, a ball slida'bly mounted on said member, a socket mounted on said steering aeroplane and engaging said ball to provide universal movement for said steering aeroplane, a pair of staysfor limiting the upward movement of said steering aeroplane on said member and secured to said steering aeroplane at points located below the center of said ball and respectively in front of and behind said ball and in the fore and aft plane of symmetry of the steering aeroplane, whereby said steering aeroplane will be normally urged into such position that its plane of symmetry will be coincident'with said upright member.

12. In a flying machine, the combination of a main supporting aeroplane structure, a steering aeroplane connected therewith and coacting therewith in the support of the machine, means providing for universal movement of said steering aeroplane with respect to said main aeroplane structure, a steering member mounted to rotate about a longitudinal axis and to oscillate about a transverse axis, four cables connected to said member at points symmetrically arranged with respect to the center of oscillation of said member and having their opposite ends connected to said steering aeroplane at" points symmetrically arranged with respect to the. center of universal movement thereof, whereby the oscillation or rotation of said member will cause corresponding movements of said steering aeroplane, a relatively movable part carried by said member, and a pair of cables connecting said part with said steering aeroplane at points symmetrically located with respect to the center of universal movement thereof and adapted through the movement of said part relatively to said member to tilt said steering aeroplane laterally on its center of universal movement.

13. In a flying machine, the combination of a pair of main supporting aeroplanes located one above the other and symmetrical with respect to a vertical plane parallel with the line of flight, said. aeroplanes being of opposite dihedral form with respect to each other and one of said aeroplanes having its lateral end portions disposed at dihedral angles different from its middle portions,

and a horizontally disposed steering aeroplane spaced rearwardly away from said main supporting aeroplanes along the line of flight and so mounted with respect to said main aeroplanes that during normal flight its center of effort will be above a line "through thecenter of effort of said main aeroplanes and parallel with the direction of normal forward flight, said steering aeroplane being rotatable about a vertically disposed axis, said steering aeroplane having its lateral portions disposed in upwardlydiverging dihedral relation to each other, and means adapted through the pressure of the air on .said steering aeroplane to nor mally urge said steering-aeroplane to a cer-. tain predetermined position with respect to said frame.

14. In a flying machine, the combination.

with an aeroplane structure, of a steering plane mounted thereon for relative angular movement, and a pair of stays spaced from the axis of such angular movement'connecting saldsteering plane w th sa1d structure and adapted through the pressure of the air on said steering plane to normally urge it to a certain definite normal position for horizontal flight, said stays being located respectively fore and aft of the center of universal movement and being relatively adjustable to vary-the normal fore and aft disposition of said steering plane. e Signed at Chicago this 2nd day of July 1910. i JAMES S. STEPHENS. Witnesses? I EUGENE-A.-RUMMLER,

Many M. DILLMAN'. 

